module M {
  f1 () : void
  {
    foreach (_ in null) { } // E: collection in foreach must be an array or type implementing enumerator pattern, the compiler has no idea what the type might be
  }

  f2 () : void
  {
    foreach (_ in 3) { } // E: expected System.Collections.IEnumerable, got int in type-enforced expression
  }

  f3 () : void
  {
    def f (x) {
      foreach (_ in x) { } // E: collection in foreach must be an array or type implementing enumerator pattern, the compiler has no idea what the type might be
    }
  }
}